Considerable research and resources have been devoted to oncology and antitumor measures including chemotherapy. Tumors inflict mammals and man with a variety of disorders and conditions including various forms of cancer and resultant cancerous cachexia, which term refers to the symptomatic discomfort that accompanies the infliction of a mammal with a tumor. Such symptoms include weakened condition of the inflicted mammal as evidenced by weight loss, etc. The seriousness of cancer is well known since cancer is a major cause of death in man. While certain methods and chemical compositions have been developed which aid in inhibiting, remitting, or controlling the growth of tumors new methods and antitumor chemical compositions are needed.
Viral diseases also inflict man, plants, insects and animals. The prevention and control of viral diseases has important health and economic implications. Viral diseases contribute to inflictions in humans including the common cold, herpes, acquired immune deficiency syndrome (AIDS), and cancer, so the importance of their control is obvious. Also important is the control of viral diseases in animals for economic and other reasons, e.g., the ability of such animals to become virus reservoirs or carriers which facilitate the spreading of viral diseases to humans. Viral plant diseases have been known to have a disruptive effect on the cultivation of fruit trees, tobacco, and various vegetables. Insect viral diseases are also of interest because of the insects' ability to transfer viral diseases to humans.
The prevention and control of viral diseases is thus of prime importance to man, and considerable research has been devoted to antiviral measures. Certain methods and chemical compositions have been developed which aid in inhibiting, controlling, or destroying viruses, but additional methods and antiviral compositions are needed.
It has been found that some natural products and organisms are potential sources for chemical molecules having useful biological activity of great diversity. Marine life has been the source for the discovery of compounds having varied biological activities. Some of the United States patents which have issued for such inventions are as follows: U.S. Pat. No. 4,548,814 for didemnins, having antiviral activity, were isolated from a marine tunicate; U.S. Pat. No. 4,729,996 discloses compounds, having antitumor properties, that were isolated from marine sponges Teichaxinella morchella and Ptilocaulis walpersi; U.S. Pat. No. 4,80,590 discloses compounds, having antiviral, antitumor, and antifungal properties, isolated from the marine sponge Theonella sp.; and U.S. Pat. No. 4,737,510 discloses compounds, having antiviral and antibacterial properties, isolated from the Caribbean sponge Agleas coniferin. Clearly, marine sponges have proved to be a source of biological compounds, and a number of publications have issued disclosing organic compounds derived from marine sponges, including Scheuer, P. J. (ed.) Marine Natural Products, Chemical and Biological Perspectives, Academic Press, New York, 1978-1983, Vol I-V; Faulkner, D. J., (1984) Natural Products Reports 1:551-598; Natural Products Reports (1986) 3:1-33; Natural Products Reports (1987) 4:539-576; Natural Products Report (1988) 5:613-663; J. Am. Chem. Soc. (1985) 107:4796-4798.
In addition to marine sponges, many other types of marine organisms have been investigated for biologically active compounds. The following publications also describe compounds obtained from marine organisms:
Castiello, D., G. Cimino, S. De Rosa, B. De Stefano, and G. Sodano (1980) "High molecular weight polyacetylenes from the nudibranch Peltodoris atromaculata and the sponge Petrosia ficiformis," Tetrahedron Letters 21:5047-5050; PA0 U.S. Pat. No. 4,548,814 for didemnins from a marine tunicate; and PA0 Moore, R. E., and M. Entzeroth (1988) "Majusculamide D and deoxymajusculamide D, two cytotoxins from Byngbya majuscula," Phytochemistry 27(10):3101-3103.